A building anchor typically comprises an elongate rod threaded at both ends so that it may be inserted within a hole formed along the length of a wall of a structure such as a building and onto which thrust plates may be then fitted and tightened by nuts to tension the anchor and thereby strengthen the wall against failure. Where the building is generally box-like two or more such anchors are secured between corners of the building along each wall, thereby considerably stiffening it and decreasing the likelihood of structural failure in the event of an earthquake or other such vibrational event. However, a problem with this known kind of reinforcement is that the anchor rods are so strong relative to the structures in which they are placed that during a severe earthquake or after a series of earth tremors it has been found that they remain in position even when the surrounding wall being reinforced has been caused to move by the tremors such that, typically on the leeward side of the epicenter of an earthquake, such walls are still prone to collapsing outwardly away from the anchors. In addition, the rigidity of the anchors along their major axis does not prevent torsional movement of a target structure within which they are placed, such that cracking of walls can occur diagonally which can also cause great damage even if the building remains upright afterwards.